The Syrian Observatory for Human Rights said it was the highest civilian death toll in Idlib since the region was designated in May as one of Syria's "de-escalation" zones under an accord between regime allies Russia and Iran, and rebel backer Turkey.

"The air raids struck several locations and villages in the district of Jisr Al Shughur, leaving 37 dead among civilians, including 12 children," observatory chief Rami Abdel Rahman told AFP, updating an earlier toll of 27 dead.

After several months of calm, Idlib province has for the past two weeks been the target of heavy air strikes by the regime and its Russian allies, following an extremist assault in neighbouring Hama province also covered by the de-escalation accord for Syria's war that has cost more than 330,000 lives since 2011.

The Daesh extremist group has no fighters in Idlib.

Syria’s exiled opposition blamed Russia and the Syrian regime for what it called the “criminal” bombing, according to a statement.

In what the Istanbul-based National Coalition branded “war crimes”, hospitals, medical installations, schools and civil defence facilities had been hit, it said.

Also on Monday, the US-backed Syrian Democratic Forces (SDF) militia accused Russia of killing one of its fighters and wounding others in strikes on a gas facility it captured two days earlier from the Daesh terror group in eastern Syria.

“Russian air strikes and mortar fire hit the Conoco gas plant where a large number of our forces are stationed,” SDF spokeswoman Lilwa Abdallah told AFP.

A statement issued later by the militia said one fighter had been killed and six wounded in the bombing.

Moscow neither confirmed nor denied the report, noting only that Russian warplanes were carrying out strikes on “terrorist sites” in support of regime operations against the extremists in Deir Ezzor province.

The Jordan Times

The Jordan Times is an independent English-language daily published by the Jordan Press Foundationsince October 26, 1975. The Jordan Press Foundation is a shareholding company listed on the Amman Stock Exchange.